CHD Elektroservis K770-KBD User manual

K770
K770K770
K770-
--
-KBD
KBDKBD
KBD
MIDI Interface for
MIDI Interface forMIDI Interface for
MIDI Interface for
Korg 770 / 700S / 900PS Keyboard
Korg 770 / 700S / 900PS KeyboardKorg 770 / 700S / 900PS Keyboard
Korg 770 / 700S / 900PS Keyboard
Model 8
Model 8Model 8
Model 8-
--
-430
430430
430
Version 1.0
Version 1.0Version 1.0
Version 1.0
Installation Manual for Korg 770
Installation Manual for Korg 770Installation Manual for Korg 770
Installation Manual for Korg 770
© 2019 CHD Elektroservis
© 2019 CHD Elektroservis© 2019 CHD Elektroservis
© 2019 CHD Elektroservis

Korg 770 MIDI Interface
Korg 770 MIDI InterfaceKorg 770 MIDI Interface
Korg 770 MIDI Interface
K770
K770 K770
K770-
--
-KBD
KBDKBD
KBD
Installation M Installation MInstallation M
Installation Manual
anualanual
anual
8
88
8-
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-430 / v. 1.00
430 / v. 1.00430 / v. 1.00
430 / v. 1.00
Copyright © 2019 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
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Contents:
Contents:Contents:
Contents:
1
11
1
GENERAL INFORMATION
GENERAL INFORMATIONGENERAL INFORMATION
GENERAL INFORMATION ................................
................................................................
................................................................
................................................................
................................................................
................................................................
................................................................
................................................................
................................ 3
33
3
1.1 MIDI INTERFACE KIT PARTS............................................................................................................................. 3
2
22
2 MIDI INTERFACE INSTALLATION
MIDI INTERFACE INSTALLATIONMIDI INTERFACE INSTALLATION
MIDI INTERFACE INSTALLATION ................................
................................................................
................................................................
................................................................
................................................................
................................................................
.......................................................
..............................................
....................... 4
44
4
2.1 OPEN THE INSTRUMENT................................................................................................................................. 4
2.2 DRILLING OF HOLES FOR MIDI SOCKETS............................................................................................................ 5
2.3 MIDI SOCKETS MOUNTING ............................................................................................................................. 6
2.4 DRILLING OF HOLES FOR BUTTON AND INDICATION LED..................................................................................... 7
2.5 BUTTON AND INDICATION LED MOUNTING...................................................................................................... 7
2.6 POWER SUPPLY CABLE MOUNTING.................................................................................................................. 8
2.7 KEYBOARD CONTROL SIGNALS CABLE MOUNTING ............................................................................................. 8
2.8 THE INTERFACE BOARD MOUNTING .............................................................................................................. 10
2.9 INTERFACE ADJUSTMENT ............................................................................................................................. 12
2.10 FINISHING OF THE INSTALLATION.................................................................................................................. 13
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3 INSTALLATION TIPS
INSTALLATION TIPSINSTALLATION TIPS
INSTALLATION TIPS ................................
................................................................
................................................................
................................................................
................................................................
................................................................
................................................................
................................................................
......................................
............
...... 14
1414
14
3.1 MIDI – THRU/OUT OUTPUT .......................................................................................................................... 14
3.2 USAGE OF ORIGINAL DIN SOCKETS ................................................................................................................ 14
3.3 RESET BUTTON AND INDICATION LED ............................................................................................................ 15

Korg 770 MIDI Interface
Korg 770 MIDI InterfaceKorg 770 MIDI Interface
Korg 770 MIDI Interface
K770
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--
-KBD
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KBD
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1
GENERAL INFORMATION GENERAL INFORMATIONGENERAL INFORMATION
GENERAL INFORMATION
Figure 1.1
Figure 1.1 Figure 1.1
Figure 1.1 –
––
– Connection to instrument circuits
Connection to instrument circuits Connection to instrument circuits
Connection to instrument circuits
K770-KBD MIDI interface controls VCO and GATE
generator of the Korg 770 synthesizer. Simplified block
schematics of the interface installation in the
instrument shows fig. 1.1.
The interface board looks very similarly for Korg 770,
700S, 900PS and M500 but there are a differences in
some components. It is recommended to check if you
have the correct model. The instrument model
identification label on the interface board (see fig. 1.2)
specifies the Korg instrument type: K770 is interface
for Korg 770, 700S and 900PS, KM500 is interface for
Korg M500 Micropreset.
Figure 1.2
Figure 1.2 Figure 1.2
Figure 1.2 –
––
– Identification labels
Identification labels Identification labels
Identification labels
The interface firmware can be revised. Actual version of the
firmware is printed on the identification label on the interface’s
processor (see fig. 1.2). It is also possible to read the actual
version of firmware from the interface by MIDI System Exclusive
message.
1.1
1.11.1
1.1
MIDI I MIDI IMIDI I
MIDI INTERFACE KIT PARTS
NTERFACE KIT PARTSNTERFACE KIT PARTS
NTERFACE KIT PARTS
MIDI interface kit contents all necessary parts for installation
incl. all support and coupling elements. The delivery also
includes both installation and operation manuals in printed
form. Please check if the delivery is complete before the
installation (see fig. 1.1.1).
Figure 1.1.1
Figure 1.1.1 Figure 1.1.1
Figure 1.1.1 –
––
– Parts of the interface kit
Parts of the interface kit Parts of the interface kit
Parts of the interface kit
The K770-KBD interface kit
delivery contents:
(1) MIDI Interface board
(2) 2x DIN-5 socket with cable
(3) Bunched cables for power
supply
(4) Bunched cables with
button and LED
(5) Bunched cables of
keyboard control signals
(6) Coupling elements (LED
holder, screws, nuts,
washers, insulation tube
and tightening strips)
(7) Owner’s and Installation
manuals in printed form

Korg 770 MIDI Interface
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Korg 770 MIDI Interface
K770
K770 K770
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-KBD
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KBD
Installation M Installation MInstallation M
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2
MIDI INTERFACE INSTALLATION MIDI INTERFACE INSTALLATIONMIDI INTERFACE INSTALLATION
MIDI INTERFACE INSTALLATION
Mounting the interface in the Korg 770 synthesizer is very easy. If you follow the instructions from this manual,
there should be no major problems during the installation. The interface installation procedure is thoroughly
described in the following chapters. Please follow these instructions accurately to avoid any damage of the
instrument.
Attention! Disconnect the instrument form the mains prior to the installation. There is a risk of the
Attention! Disconnect the instrument form the mains prior to the installation. There is a risk of the Attention! Disconnect the instrument form the mains prior to the installation. There is a risk of the
Attention! Disconnect the instrument form the mains prior to the installation. There is a risk of the
electric shock!
electric shock!electric shock!
electric shock!
Attention! Observe precautions for handling electrostatic discharge sensitive devices!
Attention! Observe precautions for handling electrostatic discharge sensitive devices!Attention! Observe precautions for handling electrostatic discharge sensitive devices!
Attention! Observe precautions for handling electrostatic discharge sensitive devices!
The produce
The produceThe produce
The producer is not responsible for any eventual mechanical or electrical damage of the Korg
r is not responsible for any eventual mechanical or electrical damage of the Korg r is not responsible for any eventual mechanical or electrical damage of the Korg
r is not responsible for any eventual mechanical or electrical damage of the Korg
instrument caused by the infringement of the described installation procedure or by careless
instrument caused by the infringement of the described installation procedure or by careless instrument caused by the infringement of the described installation procedure or by careless
instrument caused by the infringement of the described installation procedure or by careless
manipulation during the installation of the MIDI interface!
manipulation during the installation of the MIDI interface!manipulation during the installation of the MIDI interface!
manipulation during the installation of the MIDI interface!
It is recommended t
It is recommended tIt is recommended t
It is recommended to calibrate the instrument accordingly to the instructions in service manual of the
o calibrate the instrument accordingly to the instructions in service manual of the o calibrate the instrument accordingly to the instructions in service manual of the
o calibrate the instrument accordingly to the instructions in service manual of the
instrument prior the interface installation. This ensures trouble
instrument prior the interface installation. This ensures troubleinstrument prior the interface installation. This ensures trouble
instrument prior the interface installation. This ensures trouble-
--
-free operation of the interface.
free operation of the interface.free operation of the interface.
free operation of the interface.
2.1
2.12.1
2.1
OPEN THE INSTRUMENT OPEN THE INSTRUMENTOPEN THE INSTRUMENT
OPEN THE INSTRUMENT
a) Unscrew four screws on the bottom side of the instrument (fig. 2.1.1). Keep the screws. They will be used
again after the MIDI kit installation is finished.
b) Remove the front panel - cover under the instrument’s keyboard (fig. 2.1.2).
Figure 2.1.1
Figure 2.1.1Figure 2.1.1
Figure 2.1.1
Figure 2.1.2 Figure 2.1.2Figure 2.1.2
Figure 2.1.2
c) Unscrew fifteen screws on the bottom side of the instrument (fig. 2.1.3). Keep the screws. They will be used
again after the MIDI kit installation is finished.
Figure 2.1.3
Figure 2.1.3Figure 2.1.3
Figure 2.1.3
Figure 2.1.4 Figure 2.1.4Figure 2.1.4
Figure 2.1.4

Korg 770 MIDI Interface
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Korg 770 MIDI Interface
K770
K770 K770
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-KBD
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KBD
Installation M Installation MInstallation M
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Figure 2.1.5
Figure 2.1.5Figure 2.1.5
Figure 2.1.5
d) Unscrew ten screws on the rear side of the instrument
(fig. 2.1.4). Keep the screws and four washers. They will be
used again after the MIDI kit installation is finished.
e) Place the instrument on the side and gently unclip the
bottom part of the cover (fig. 2.1.5). All instrument’s parts
and boards needed for the interface installation are now
accessible (fig. 2.1.6).
Figure 2.1.6
Figure 2.1.6Figure 2.1.6
Figure 2.1.6
2.2
2.22.2
2.2
DRILLING OF HOLES FOR MIDI SOCKETS DRILLING OF HOLES FOR MIDI SOCKETSDRILLING OF HOLES FOR MIDI SOCKETS
DRILLING OF HOLES FOR MIDI SOCKETS
The interface has both MIDI input and output. Only MIDI input is necessary for the basic interface operation.
MIDI output has not to be installed – see chapter 3.1. Nevertheless, having both MIDI input and output (MIDI-IN
and MIDI-THRU/OUT sockets) is more convenient for an easy integration in the more advanced MIDI system.
Figure 2.2.1
Figure 2.2.1Figure 2.2.1
Figure 2.2.1
If you prefer to maintain the vintage status of the
instrument (you may not want to drill to the
instrument’s cover), there is another way. You can use
the original DIN sockets on instrument’s rear panel (its
original functions seem to be almost useless for most
users) – see chapter 3.2.
If you decide to install MIDI sockets, the suitable place
for them is on the right side of rear panel of the
instrument under the “KORG” label (fig. 2.2.1). In that
case, you have to drill six holes to the panel.

Korg 770 MIDI Interface
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Korg 770 MIDI Interface
K770
K770 K770
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KBD
Installation M Installation MInstallation M
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a) Drill two holes with diameter 16 mm and four holes with diameter 3,2 mm to the rear panel of the
instrument as shown on fig. 2.2.2 (all dimensions are in mm). Use sharp drills and work carefully
work carefullywork carefully
work carefully so that the
cover is not scratched and other parts of the instrument are not damaged!
Figure 2.2.2
Figure 2.2.2Figure 2.2.2
Figure 2.2.2
b) Clean the edge of the holes with small rasp or tip of bigger drill from both sides of the panel after the holes
are drilled.
c) Clean all iron sawdust and raspings from the inside of the instruments
Clean all iron sawdust and raspings from the inside of the instrumentsClean all iron sawdust and raspings from the inside of the instruments
Clean all iron sawdust and raspings from the inside of the instruments, they can cause short circuits or serious
electrical damage if left inside the instrument. Please clean the instrument carefully!
2.3
2.32.3
2.3
MIDI SOCKETS MOUNTING MIDI SOCKETS MOUNTINGMIDI SOCKETS MOUNTING
MIDI SOCKETS MOUNTING
a) Pull flat connectors of MIDI cables (from the interface accessory) through 16 mm holes in the instrument’s
rear panel from outer side and insert DIN sockets into the holes. Both MIDI cables are identical and can be
swapped.
b) Fix DIN sockets to the drilled holes using screws, nuts and tooth lock washers from the interface accessory
(fig. 2.3.1).
c) It is recommended to label the DIN sockets ("MIDI IN", "MIDI THRU/OUT" for example) with self-adhesive foil
glued near the sockets (fig. 2.3.2).

Korg 770 MIDI Interface
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Korg 770 MIDI Interface
K770
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Figure 2.3.1
Figure 2.3.1 Figure 2.3.1
Figure 2.3.1
Figure 2.3.2 Figure 2.3.2 Figure 2.3.2
Figure 2.3.2
2.4
2.42.4
2.4
DRILLING OF HOLES FOR BUTTON AND INDICATION LED DRILLING OF HOLES FOR BUTTON AND INDICATION LEDDRILLING OF HOLES FOR BUTTON AND INDICATION LED
DRILLING OF HOLES FOR BUTTON AND INDICATION LED
There are two control elements on the interface - button and bi-color LED. They are not necessary for the
interface operation, so they need not to be installed (if you prefer to maintain the vintage status of the
instrument) – see chapter 3.3. Nevertheless having both of them installed is more convenient for easier device
control.
If you decide to install the LED and the button, the suitable place for them is on the left side of the front panel
(the cover under the instrument’s keyboard) near the headphones jack (fig. 2.4.1). In that case, you have to drill
two holes in the panel as shown on fig. 2.4.2 (all dimensions are in mm).
Figure 2.4.1
Figure 2.4.1Figure 2.4.1
Figure 2.4.1
Figure 2.4.2 Figure 2.4.2 Figure 2.4.2
Figure 2.4.2
a) Drill one hole with diameter 7 mm (for RESET button) and one hole with diameter 6,5 mm (for indication LED)
to the panel – see pic. 2.4.2. Use sharp drills and work carefully
work carefullywork carefully
work carefully so that the cover is not scratched during the
drilling!
b) Clean the edge of all holes with small rasp or with point of bigger drill after the holes are drilled.
2.5
2.52.5
2.5
BUTTON BUTTON BUTTON
BUTTON AND INDICATION LED MOUNTING
AND INDICATION LED MOUNTINGAND INDICATION LED MOUNTING
AND INDICATION LED MOUNTING
a) Insert LED holder (from the interface accessory) into 6,5 mm hole in the instrument’s front panel from the
outer side. Pull the lock ring of the LED holder over the supplied LED. Then insert the LED into the holder (from
inner side of the instrument’s panel) and fix it by the overthrust of the ring on the holder (fig. 2.5.1).
b) Insert button into 7 mm hole in the instrument’s panel from inner side. Fix the button to the panel with the
spring washer and nut (fig. 2.5.2).

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Figure 2.5.1
Figure 2.5.1 Figure 2.5.1
Figure 2.5.1
Figure 2.5.2 Figure 2.5.2 Figure 2.5.2
Figure 2.5.2
2.6
2.62.6
2.6
POWER SUPPLY CABLE MOUNTING POWER SUPPLY CABLE MOUNTINGPOWER SUPPLY CABLE MOUNTING
POWER SUPPLY CABLE MOUNTING
The power supply cable from the interface accessory is fitted with 3-pin flat connector (fig. 2.6.1). It is advisable
to shorten wires of this cable bunch to the required lengths as shown on fig. 2.6.1
1
11
1
. Wires of the cable bunch
must be connected to several pads at the instrument’s power supply board (fig. 2.6.2).
Figure 2.6.1
Figure 2.6.1Figure 2.6.1
Figure 2.6.1
Figure 2.6.2
Figure 2.6.2Figure 2.6.2
Figure 2.6.2
a) Solder the red wire Nr. 3
“+20V“ to “+Vcc” pad on the
instrument’s power supply
board (fig. 2.6.2). An orange
wire of original bunched cables
is already soldered here.
b) Solder the black wire Nr. 2
“GND“ to “GND” pad on the
instrument’s power supply
board (fig. 2.6.2). A black wire
of original bunched cables is
already soldered here.
c) Solder the blue wire Nr. 1 “-
10V“ to “-Vee” pad on the
instrument’s power supply board (fig. 2.6.2). Two green wires of the original bunched cables are already
soldered here.
2.7
2.72.7
2.7
KEYBOARD CONTROL SIGNALS CABLE MOUNTING KEYBOARD CONTROL SIGNALS CABLE MOUNTINGKEYBOARD CONTROL SIGNALS CABLE MOUNTING
KEYBOARD CONTROL SIGNALS CABLE MOUNTING
The keyboard control signals cable from the interface accessory is fitted with 4-pin flat connector (fig. 2.7.1).
Wires outgoing from this connector must be connected to the instrument’s keyboard and between the
instrument’s keyboard and TRIGGER (KLM42) board (fig. 2.7.2 and fig. 1.1 in chapter 1).
1
The delivered power supply cable is universal for all 770, 700S and 900PS instruments so its original length does not meet the 770 exactly.

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Figure 2.7.1
Figure 2.7.1Figure 2.7.1
Figure 2.7.1
Figure. 2.7.2
Figure. 2.7.2Figure. 2.7.2
Figure. 2.7.2
a) Unsolder hot wire of the white shielded cable (leads from the KLM42 board) from soldering lug on the side
board of the keyboard chassis (fig. 2.7.3).
b) Place heat-shrink insulation tube
φ 2 mm (from the interface accessory) on yellow wire Nr. 2 “OUT” of the
keyboard control signals cable and solder the yellow wire to white wire freed from the soldering lug (fig. 2.7.4).
Figure 2.7.3
Figure 2.7.3Figure 2.7.3
Figure 2.7.3
Figure 2.7.4 Figure 2.7.4Figure 2.7.4
Figure 2.7.4
c) Isolate the connection with the insulation tube and heat it (with a hot-flue pistol for example) until it shrinks
tightly to the cables.
d) Solder green wire Nr. 1 “IN” of the interface cable to the solder lug on the instrument’s side board (fig. 2.7.5).
e) Solder red wire Nr. 3 “REF“ of the interface cable to lug on the instrument’s keyboard where two brown
wires are already soldered (fig. 2.7.6).
f) Solder black wire Nr. 4 “GND“ of the interface cable to thick wire (common bus) of the instrument’s keyboard
– to pad where a black wire and shielding of white cable are already soldered (fig. 2.7.6).

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Figure 2.7.5
Figure 2.7.5Figure 2.7.5
Figure 2.7.5
Figure 2.7.6 Figure 2.7.6Figure 2.7.6
Figure 2.7.6
2.8
2.82.8
2.8
THE INTERFACE BOARD MOUNTING THE INTERFACE BOARD MOUNTINGTHE INTERFACE BOARD MOUNTING
THE INTERFACE BOARD MOUNTING
a) The interface board will be placed on the rear panel of the bottom metal cover of the instrument – to the left
of the power supply board (fig. 2.8.1).
Figure. 2.8.1
Figure. 2.8.1Figure. 2.8.1
Figure. 2.8.1
b) Cleanse the part of rear panel inside of the instrument for the interface board placement (fig. 2.8.1). Use a
chemical cleaner to remove all dirt and grease.
c) Remove the protective foil form the self-adhesive supports of the interface board (fig. 2.8.2).
Figure 2.8.2
Figure 2.8.2Figure 2.8.2
Figure 2.8.2
Figure 2.8.3 Figure 2.8.3 Figure 2.8.3
Figure 2.8.3

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11
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d) Attach the interface board to the instrument’s cover so that the board side with two connectors X4 (“KBD”)
and X5 (“PWR”) points to the right, towards the power supply board as shown on the figure 2.8.3. Than fix the
self-adhesive supports by pressing down to the cover.
e) Plug the 3-pin connector of the bunched cables lead from the power supply board to X5 (“PWR”) plug head
on the interface board. Orientation of the connector is given by the connector lock so it cannot be plugged
reversely (fig. 2.8.4).
f) Plug 4-pin connector of the bunched cables lead from keyboard to X4 (“KBD”) plug head on the interface
board. Orientation of the connector is given by the connector lock again (fig. 2.8.4).
g) Plug two 3-pin connectors of the MIDI cables to X1 (“I”) and X2 (“O”) plug heads on the interface board.
Orientation of the connectors is given by the connector lock again but be sure that the connectors are not
exchanged: MIDI input must be plugged to X1 head and MIDI output to X2 head (fig. 2.8.4).
h) Plug the 4-pin connector of the bunched cables with button and LED to X3 (“CTRL”) plug head on the
interface board. Orientation of the connector is given by the connector lock again (fig. 2.8.4).
Figure 2.8.4
Figure 2.8.4Figure 2.8.4
Figure 2.8.4
Figure 2.8.5
Figure 2.8.5Figure 2.8.5
Figure 2.8.5
i) Align new keyboard control cable
(“KBD”) and fix it together to the original
keyboard cables with four plastic stripes
from the interface accessory (fig. 2.8.5).
j) Align new cable with LED and button
(“CTRL”) and fix it together to the
original cable leading to headphones jack
with two plastic stripes from the
interface accessory (fig. 2.8.5).

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2.9
2.92.9
2.9
INTERFACE ADJUSTMENT INTERFACE ADJUSTMENTINTERFACE ADJUSTMENT
INTERFACE ADJUSTMENT
Figure 2.9.1
Figure 2.9.1Figure 2.9.1
Figure 2.9.1
There are two variable resistors on the interface board
labeled “OFFSET” and “RANGE” (fig. 2.9.1). They must be
adjusted before the interface is used. Adjustment
procedure is following
2
22
2
:
a) Leave the instrument open so there is an access for the
variable resistors adjustment with a small screwdriver.
b) Connect MIDI output of your MIDI master keyboard (or
PC / sequencer / DAW) to MIDI input of the interface
3
33
3
.
c) Connect audio output of the instrument to a tuner or to
a frequency meter.
d) Set all controllers on the instrument’s panel to a clear sound without any modulation:
• VCO I. Æ PITCH = 0, OCTAVE = 8’, MODE = Saw
• MIXER Æ knob fully counterclockwise, switch to VCO I.
• PORTAMENTO Æ switch to middle position (off)
• VCF Æ LOW PASS = 10, HIGH PASS = 0, EXPAND L.P = OFF, EXPAND H.P = OFF, BRIGHT = OFF, LFO = OFF
• ENVELOPE GENERATOR Æ ATTACK = 0, SINGING = 8, RANGE = x1, MODE = SUSTAIN, TRIGGER = KEY
• VCO MODULATOR Æ BEND switch to middle position (off), VIBRATO switch to middle position (off)
Positions of other controllers on instrument’s panel are not significant.
e) Plug instrument's power supply cable to a mains socket and switch the instrument on by main switch joined
with the VOLUME knob. Attention
Attention Attention
Attention -
--
- work very carefully during whole adjustment procedure
work very carefully during whole adjustment procedure work very carefully during whole adjustment procedure
work very carefully during whole adjustment procedure -
--
- there is a risk of
there is a risk of there is a risk of
there is a risk of
electric shock!
electric shock!electric shock!
electric shock!
f) Now, the interface is in "Stand-by" mode - the interface’s indication LED is off. If not, press the "RESET"
button of the interface.
g) Wait a few minutes
Wait a few minutesWait a few minutes
Wait a few minutes to stabilize the temperature of all instrument circuits.
h) Measure the voltage between pins of the "TP" jumper head (fig. 2.9.1) with a quality digital multimeter. It
should be zero volts exactly. If it is not, adjust it with "OFFSET” variable resistor on the interface board (fig.
2.9.1).
i) Press the highest key on the instrument’s keyboard (i.e. C4) - indication bi-color LED remains off.
j) Measure the output tone frequency by the tuner (frequency meter). It should be 2093 Hz approx. Remember
the measured tone frequency. Then release the C4 key.
k) Press the C4 key on the master keyboard (i.e. send MIDI Note Nr. 96 to the interface) and hold it. The
indication LED will light in green.
l) Check the output tone frequency by the tuner (frequency meter) again. It must be the same as the frequency
measured in paragraph j). If it is not, adjust it with "RANGE” variable resistor on the interface board (fig. 2.9.1).
m) Release the C4 key on the master keyboard. Switch the instrument off and disconnect the power supply
disconnect the power supply disconnect the power supply
disconnect the power supply
cable from mains socket
cable from mains socketcable from mains socket
cable from mains socket.
2
It is suppossed that the interface is in "Factory Reset" status before the adjustment procedure. If it is not, send the F0 00 20 21 7F 54 50 03 7F 5A
F0 00 20 21 7F 54 50 03 7F 5A F0 00 20 21 7F 54 50 03 7F 5A
F0 00 20 21 7F 54 50 03 7F 5A
F7 [hex]
F7 [hex]F7 [hex]
F7 [hex] SysEx message to the intarface first.
3
Set transmit MIDI Channel to number 1 on the master keyboard.

Korg 770 MIDI Interface
Korg 770 MIDI InterfaceKorg 770 MIDI Interface
Korg 770 MIDI Interface
K770
K770 K770
K770-
--
-KBD
KBDKBD
KBD
Installation M Installation MInstallation M
Installation Manual
anualanual
anual
8
88
8-
--
-430 / v. 1.00
430 / v. 1.00430 / v. 1.00
430 / v. 1.00
Copyright © 2019 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
13
1313
13
2.10
2.102.10
2.10
FINISHING OF THE INSTALLATION FINISHING OF THE INSTALLATIONFINISHING OF THE INSTALLATION
FINISHING OF THE INSTALLATION
Now it is necessary to assembly all instrument parts of the instrument together. It is a reverse procedure than
described in chapter 2.1.
a) Place the bottom cover back to the instrument (fig. 2.10.1). Be sure that no cables are pinched under the
cover!
b) Fix the bottom cover with original ten screws to the instrument from the rear side of the instrument (fig.
2.10.2). Do not forget to place plastic washers under four top screws.
Figure 2.10.1
Figure 2.10.1 Figure 2.10.1
Figure 2.10.1
Figure 2.10.2 Figure 2.10.2 Figure 2.10.2
Figure 2.10.2
c) Fix the bottom cover with original fifteen screws (fig. 2.10.3).
d) Place the front panel (cover under the instrument’s keyboard) back to the instrument and fix it with original
four screws (fig. 2.10.4).
Figure 2.10.3
Figure 2.10.3 Figure 2.10.3
Figure 2.10.3
Figure 2.10.4 Figure 2.10.4 Figure 2.10.4
Figure 2.10.4
The installation of the MIDI interface kit is now finished and the Korg 770 instrument is prepared for MIDI
communication.
Please read carefully user manual of the interface before usage of modified instrument.
Please read carefully user manual of the interface before usage of modified instrument.Please read carefully user manual of the interface before usage of modified instrument.
Please read carefully user manual of the interface before usage of modified instrument.

Korg 770 MIDI Interface
Korg 770 MIDI InterfaceKorg 770 MIDI Interface
Korg 770 MIDI Interface
K770
K770 K770
K770-
--
-KBD
KBDKBD
KBD
Installation M Installation MInstallation M
Installation Manual
anualanual
anual
8
88
8-
--
-430 / v. 1.00
430 / v. 1.00430 / v. 1.00
430 / v. 1.00
Copyright © 2019 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
1
4
141
4
14
3
33
3
INSTALLATION TIPS INSTALLATION TIPSINSTALLATION TIPS
INSTALLATION TIPS
3.1
3.13.1
3.1
MIDI MIDI MIDI
MIDI –
––
– THRU/OUT OUTPUT
THRU/OUT OUTPUT THRU/OUT OUTPUT
THRU/OUT OUTPUT
K770-KBD interface has both MIDI input and output. However, only MIDI input is necessary for basic operation
of the interface (i.e controlling the instrument by MIDI commands). MIDI THRU/OUT output connector need not
to be installed at all. If you don’t require transfer of MIDI data to another MIDI devices (THRU function ) or
reverse communication of the interface with host system (OUT function). In such case, X2 connector (labeled
“O
OO
O”) on the interface board will remain unused (see pic. 3.1).
Figure 3.1
Figure 3.1Figure 3.1
Figure 3.1
3.2
3.23.2
3.2
USA USAUSA
USAGE OF ORIGINAL DIN SOCKETS
GE OF ORIGINAL DIN SOCKETSGE OF ORIGINAL DIN SOCKETS
GE OF ORIGINAL DIN SOCKETS
Figure 3.2.1
Figure 3.2.1Figure 3.2.1
Figure 3.2.1
You can use the original DIN sockets placed on rear
panel of the instrument as the MIDI sockets (fig. 3.2.1).
In that case, you have to unsolder all wires and the
resistor from the original sockets! It is recommended
to label the wires prior the unsoldering so that they
can be easily recognized later. After the wires
unsoldering, insulate them (their stripped ends)
reliably e.g. with heat-shrink insulate tubes or with
insulating tape. They must not be connected with
another components or mechanical parts!
Then cut out DIN sockets from the interface’s MIDI
cables and solder wires of the MIDI cables to original DIN sockets (to the same pins!) on the instrument panel –
see fig. 3.2.2. The wires have to be extended to reach the original DIN sockets.
Figure 3.2.2
Figure 3.2.2Figure 3.2.2
Figure 3.2.2

Korg 770 MIDI Interface
Korg 770 MIDI InterfaceKorg 770 MIDI Interface
Korg 770 MIDI Interface
K770
K770 K770
K770-
--
-KBD
KBDKBD
KBD
Installation M Installation MInstallation M
Installation Manual
anualanual
anual
8
88
8-
--
-430 / v. 1.00
430 / v. 1.00430 / v. 1.00
430 / v. 1.00
Copyright © 2019 CHD Elektroservis. All rights reserved.
No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
15
1515
15
3.3
3.33.3
3.3
RESET BUTTON AND INDICATION LED RESET BUTTON AND INDICATION LEDRESET BUTTON AND INDICATION LED
RESET BUTTON AND INDICATION LED
Installation of the reset button and indication LED isn’t necessary as well. You don´t need to install this bunched
cables if you don’t want to damage the instrument’s panel by drilling. In such case, X3 connector (labeled
“CTRL
CTRLCTRL
CTRL”) will remain unused (see fig. 3.1).
It is also possible to install only the indication LED on instrument’s panel. In such case, disconnect the button
from bunched cables (cut-off yellow and black wires as shown on fig. 3.3).
If the button is not installed, the interface operation is unaffected. The only limitation is that the reset of the
interface can be done only by turning the instrument off and on or by MIDI commands sent to the interface
(see user manual of the interface).
Figure 3.3
Figure 3.3Figure 3.3
Figure 3.3
This manual in PDF form is available at manufacturer’s web pages.
This manual in PDF form is available at manufacturer’s web pages.This manual in PDF form is available at manufacturer’s web pages.
This manual in PDF form is available at manufacturer’s web pages.
KORG 770 / 700S / 900PS MIDI Interface
Model K770-KBD, Nr. 8-430, ver. 1.00
Document: 843010-1_instal
Manufacturer: CHD Elektroservis, Czech Republic
www.chd-el.cz [e-mail]